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            color: red;
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    asdfa
    <div>aaa</div>

    <script>
        // filter:grayscale(1); /
        // document.documentElement.style.filter = 'grayscale(1)'
        // 判断当前日期是不是8月30

        // 获取的电脑的当前时间
        var date = new Date();
        var m = date.getMonth() + 1;// 从零开始
        var d = date.getDate()
        if (m == 8 && d == 30) {
            document.documentElement.style.filter = 'grayscale(1)'
        }
    </script>
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